Ford Repair Questions? Ask a Mechanic for Answers ASAP
Do you have a good scan tool to check for codes and shift signals?
It is very common for the GEM on this model of truck to corrode and cause the 4wd selector to not work correctly. It's possible that the GEM was the cause of initial problem and is not also causing the switch to not work. The GEM is on the back of the fuse box and often gets water damaged from leaky windshields.
Please let me know if you need any additional info.
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